Furnace



Patented June 1, 1948 2,442,460 FURNA Rudolph Leonard Hasche, JohnsonCity, Tenn, assigiior "to" "Tennessee Eastn'ittii o'orpo at Kingsporlt:Tenin, a corporation "of Virginia isetiee eter- 9er a. e rie flafieeeet;rol i (01. 23-277) Mrinv i ien ela e t eee eretivefuni ces, 211., ur het a pr se. ases to be that is, furnaces wh ch operate upena recurringtreated" haters-es iiift t ss ee; l et egg a eyileand whichjheat. a s,to be processed, in supply pip 21 nowiiipwardiy-thro the slotsalregenerativefmassofheatfrefractorymaterial; '1' The; cycleincludesal'firiiiheriod; during which heat is iniparteicllltothe mas'sfromshctcombustio'n products'flfwhich ar passedfi 'a,'posit ivedirection, forexample, downwardly, through passages mat n the or ha i res Of transferring heat units from the hotcombustion products to themass, ahdjal'treatihgj'i eriom in which a gaswhichitis desired to. heatispassed in, a negative "direction, for "'examme, upwardly, through thepassages.

It is an object'o'f the invention to provide a i y of the asespa sihe; 1at llv h ei sh' ie regenerative mass having passa s so f rmed slotsin.these tion. ldnfissthe. tee iih .nette that. the sase e d oductst-cqm qn have over the velocitylin t es ot o lg ti lhhutl a variablemass velocity as they flow through the also provide a greaterfheatstoragej cap c ty, pass s, m v fast r in t up pa t f th around each slotin proportion to the area of passages than they do in the lower. theslot in the section l4 than I do in the section The a a ta es attainedby t s fo of D l2. For example, in the section I4, the slots may sagewill be made evident hereinafter. be A wide and the walls between theslots In the drawing, which is for illustrative pur- 1 thick, or thewalls are five times as thick D0568 y, 5 as the slots are wide; in thesection 13 the slots Fig. 1 is a vertical section through a preferredmay be wide and the walls 1%" thick, or r o furnace embodying myinvention; and the walls are three times as thick as the slots are Fig.2 is a horizontal section on a plane identiwide; and in the section [2the Slots may be' /z" fied by the line 2-2 of Fig. 1, this section beingwide and the walls 1" thick, or the walls are Viewed in the direction ofthe arrows adjoining only twice as thick as the slots are wide. The

that line. gases move upwardly twice as fast in the section In thefurnace illustrated by the drawing, a 14 as they do in the section [2. ee e at ve ss of eat resistant t a This construction is of considerablevalue when for p Carbcrlmdum bricks, is divided the gases react in thesection I4 and absorb heat roughly into three sections Whose length isindiduring the reaction, for example, when the furcated by thedimensions l2, l3, and IA. The mass nace is used to produce acetylene,ethylene, or is cylindrical, and the bricks are so laid that similarhydrocarbons from stock hydrocarbon a plurality of open slots orpassages 15 are formed raw materials delivered through the pipe 2|. Intherein, these passages connecting a primary such operations thereaction absorbs heat and space It at one end of the mass II with a sec-40 takes place only after the gases reach a m1n1mum ondary space I! atthe other end of the m critical temperature somewhere in their upward Inthe furnace shown, the slots are vertical, but passage through t e S sThe gases enter my invention is equally applicable to furnaces Tthese510178 at atmospheric p e) in which the slots are horizontal or extendin emerge a a p atu o p haps 0 Ff. any direction. The words up and doware The reaction may not start to take place until used hereinafter todescribe a vertical furnace, the gases are quite 0 3 s t p t d and notas words limiting my invention to any durirlg t r a i n h at st be ap dy an di t disposition of t Slots continuously supplied to enable it tocontinue as The furnace shown operates on a recurrent the Conversionebeorbs large amounts of heatcycle which includes a firing period and atreat- 5 The Speed Wlth which the conversion takes p e ing period, eachof which may have a duration of is p y p p t t0 the p e with Whlchperhaps one minute. During the firing period, hot this heat can besuppll d- Y makmg t 510115 products of combustion produced in acombustion narrow and the walls thick, I provide more heat chamber Is byburners l9 flow downwardly storage capacity in the section It than inthe through the slots [5 and escape through a flue section l2 and getthe heat into the gas faster than with Wider slots and thinner walls. Inproducing acetylene, the gas need be in the reaction zone less thanone-tenth of a second, which is important, as the acetylene is atransient product and changes to undesired products very rapidly. Byusing a relatively high velocity in the zone l4 and rapidly cooling thegases in the boiler 23, I prevent a large part of such undesiredreactions.

The capacity of any such furnace is also an inverse function of thepressure drop through the mass II; the higher this drop, the lower thecapacity of the furnace is. By making the slots in the section I l ofthe proper size to produce the proper reaction, and by making the slotsin the sections l3 and I 2 wider, the pressure drop is reduced from thatwhich would occur if the slots I 5 were the same size in the sections l3and I2 that they are in the section It.

In making acetylene, the top or hot end of the regenerative mass may be3000 F. and the bottom or cold end only 900 F.

A very important advantage of increasing velocity and heating theregenerative mass from bottom to top is the accelerated heat requirementin the treatment of the charging stock as the temperature is raised. Theideal condition is approached since increasing the velocity increasesalmost proportionately the heat transfer from the regenerative mass tothe hydrocarbon undergoing treatment, and the greater mass of refractorysupplies the required heat. The same relative advantages are realizedduring the heating cycle. Requisite amounts of heat are stored in theproper portions of the furnace.

Other structural features which may be employed to advantage inconjunction with the apparatus of the present invention are shown and 4described in applicant's copending applications Serial No. 633,839, newPatent No. 2,432,885, issued December 16, 1947, and Serial No. 633,843,both filed December 8, 1945.

I claim as my invention:

A regenerative furnace comprising a first chamber providing a primaryspace; an inlet communicating with said first chamber for admitting gasto be treated during a treating cycle;

an outlet communicating with said first chamber for the escape ofproducts of combustion durin a heating cycle; a second chamber spacedfrom said first chamber, forming a. substantially annular combustionspace; a plurality of burners opening into said combustion space; and anouter shell enclosing an elongated upright regenerative mass havingcontinuous rectangular passageways extending lengthwise therethrough incommunication with said annular combustion chamber at one end of saidregenerative mass and in communication with said primary space at theopposite end of said regenerative mass, said regenerative mass havinggreatest volume and greatest heat storage capacity at the end thereof inproximity to said combustion space and said rectangular passagewaysbeing of smallest cross section at the ends thereof in proximity to saidcombustion space.

RUDOLPH LEONARD I-LASCHE.

REFERENCES CITED UNITED STATES PATENTS Name Date Linder Feb. 18, 1941Number

